Abstract We report on the analysis of 2MASS near-infrared data of a sample of low-mass stars and brown dwarfs in the
Orionis cluster. Youth and cluster membership have been spectroscopically confirmed using the Li I spectral line. We find little evidence in the
colour-colour diagram for near-infrared excess emission for these cluster members. By comparison with model expectations,
at most 2 out of 34 stars show
colour consistent with a near-infrared excess. This scarcity of near-infrared signatures of circumstellar disks in the lower-mass
and substellar regimes of this cluster contrasts with findings in younger clusters, hinting at an age dependence of the disk
frequency. Taking into account the apparent cluster age, our result supports the idea of a relatively fast (few Myr) disk
dissipation and extends this conclusion to the substellar regime. We also find some evidence that, in this cluster, the disk
frequency as measured by the
-band excess may be mass dependent.